<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width,initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app"></div>
</body>
    <script src="https://unpkg.com/vue@next"></script>
    <script>
        const app = Vue.createApp({
            data() {
                return {
                    componentName:'common-demo'
                }
            },
            
               template:`
               <div @click="handleChangeClick" >切换 </div>

               <common-demo v-show="componentName === 'common-demo'" />
               <keep-alive>
                <component :is="componentName" />
                </keep-alive>
               
               `,
               methods: {
                       handleChangeClick(){
                           if(this.componentName === 'input-demo'){
                               this.componentName = 'common-demo'
                           }else{
                               this.componentName = 'input-demo'
                           }
                       }
                   },
            })
            app.component('input-demo',{
               
                template:`
                <input />
                `
            })
           app.mount("#app");
    </script>
</html>